On Wed, Jun 19, 2013 at 6:00 PM, Albe Laurenz <laurenz.albe@xxxxxxxxxx> wrote: > sachin kotwal wrote: >> While migrating my application from DB2 to PostgreSQL. >> >> I want to migrate following functions in PostgreSQL. >> >> TO_CHAR() in DB2 which can take three arguments as follows: >> >> SELECT TO_CHAR(CURRENT_DATE,'YYYY-MM-DD',112.50) FROM SYSIBM.SYSDUMMY1 >> >> I am not sure what is the purpose of third argument in TO_CHAR() function of >> DB2. >> >> I think we can create one user define function with name TO_CHAR which can >> take three argument like DB2. >> >> I want to know that if we want to create user define function TO_CHAR(). >> What should be the data type of third argument? >> >> which can handle maximum data types and more suitable for real time >> scenarios. > > Look at IBM's documentation at > http://pic.dhe.ibm.com/infocenter/db2luw/v10r1/index.jsp?topic=%2Fcom.ibm.db2.luw.sql.ref.doc%2Fdoc%2Fr0007110.html > > TO_CHAR is a synonym for VARCHAR_FORMAT. > The third argument is an optional locale name, like 'en_US', > which will be used to generate the text parts of the > format you chose. > > For a format like 'YYYY-MM-DD' this has no effect at all > and can be omitted. > > PostgreSQL has no such capability. Unless you need that and > want to code it yourself, the best solution would be to > write a function that just ignores the third argument. > Just wondering: If this particular function is to be used repeatedly in a single query, would the cost of having a wrapper function around the original function be too large? For example, if this function appears in a WHERE clause against a table containing millions of rows. -- Amit Langote -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
